1. Technical Field
The present invention generally pertains to a seat for a motor vehicle and, more particularly, to a linear seat recliner for a motor vehicle passenger seat.
2. Discussion
Most motor vehicles are equipped with seats having a seat bottom, a seat back pivotally secured to the seat bottom and a recliner mechanism for latching the seat back in a desired use position relative to the seat bottom. Generally, the recliner mechanism may be selectively actuated for adjusting the angularity of the seat back relative to the seat bottom through a range of use positions defined between an upright position and a fully reclined position. One type of recliner mechanism, referred to as a linear seat recliner, typically includes a housing and an elongated recliner rod having a first end supported by the housing. The housing is adapted to be mounted to the seat bottom frame and the second end of the recliner rod is pivotally secured to a lever arm extension of the seat back frame. A latch assembly normally functions to latch the first end of the recliner rod to the housing. Upon release of the latch assembly, linear movement of the recliner rod relative to the housing results in angular movement of the seat back relative to the seat bottom.
Conventionally, the recliner rod is constructed from a generally cylindrical smooth rod having a circular cross section. A portion of the rod is subsequently machined to include a plurality of teeth spaced along the recliner rod. Standard manufacturing techniques such as broaching require the recliner rod to be fixed while the teeth are machined. Unfortunately, the use of a generally cylindrical recliner rod make it difficult to properly form teeth on the rod. Specifically, the round rod has a tendency to rotate during machining making it difficult to properly align the teeth on the rod. Alternatively, the smooth cylindrical rod is commonly first machined to provide a planar segment and then broached in order to produce a suitable tooth width. Accordingly, it would be desirable to construct a linear seat recliner having a recliner rod with an economically manufactured, properly formed set of teeth.
In addition, many linear recliner mechanisms utilize a stop radially protruding from an end of the recliner rod in order to limit the travel of the rod in relation to the housing. While the stop is useful in limiting the travel of the seat back relative to the seat bottom, it is time consuming and therefore costly to manufacture and attach a separate stop to a recliner rod. Therefore, it would be advantageous to design a recliner rod that is capable of providing an integral stop for minimal cost.
Lastly, some recliner mechanisms do not function properly as a result of binding of the recliner rod with the mating components. These recliner rods are typically not well supported within the housing and may excessively bend due to input loading. Accordingly, a guided recliner rod with an increased resistance to bending would be a welcome improvement.